Power-press



L. L/PFEIFER. POWER PRESS.

APPLICATION FILED JUNE 2O I919.

Patented Nov. 22, 1921.

2 SHEETSSHEET 1.

Leo L. /zi el:

L. L. PFEIFER.

POWER PRESS.

.."PL|CAT|ON FILED JUNE 20, 1919.

1,397,779. Patented N v. 22, 1921.

2 SHEETSSHET 2.

0 Leo L. Pf'ef/er TET QFFHCIE.

LEO L. PFEIFEB, COLUMBUS, OHIO, ASSIGNOR TO THE JOHN W. BROWN MANU-FACTURING CUMPANY, 0F COLUMBUS, OHIO, A CORPORATION OF OHIO.

P@WEB-?RESS.

Application filed .Tune 20,

To all whom it may concern: 4

Be it known that l, LE0 L. Prnrrnn, a citizen of the United States,residing at columbus, in the county of Franklin and State of Ohio, haveinvented certain new and useful Improvements in Power-Presses, of whichthe following is a specification.

This invention relates broadly to power presses, and. has particularreference to the mechanism thereof for controlling their operation, theobject of the invention being to provide a hand operated clutchcontrolling mechanism, which, when used in conjunction with a powerpress embodying a reciprocatory die, will serve to prevent suchmovements on part of the die as would tend to injure the operator of thepress.

Another object of the invention resides in the provision of improved andnovel means for controlling the operation of the clutch structure of apower press, said means being of a hand operated character, in orderthat when the die is being reciprocated, the hands maintained inpositions clear of the the traveling die.

of the operator will be occupied in controlling the operation of saidmeans,' and in this manner the hands of the operator will be path ofWith these and othenobjects in view, as will appear as the descriptionproceeds, the

invention accordingly consists in the novel features of construction,combination of elements and arrangementof parts, hereinafter to be fullydescribed and to have the scope thereof pointed out in the appendedclaim.

In the accompanying drawings, forming a part of the presentspecification, and in which similar characters of reference denote likeand corresponding parts:

Figure 1 is a front elevation of a power press equipped with the safetycontrol mechanism comprising the present invention,

Fig. 2 is a side elevation thereof,

Fig. 3 is a fragmentary vertical sectional view taken through the clutchstructure of the press, v

F 1g. 4 is a side elevation of the structure disclosed'in Fig. 3,

Fig. 5 is a detail perspective view of the controlling mechanismcomprising the pres ent invention, and

Fig. e is a detail view of the mechanism for retaining the controllinglever in ole-- vated position,

Specification of Letters Patent.

Patented Nov. 22, 1921.

1919. serial No. 305,691.

frame 2 are guides l, in which are mounted for reciprocation the sides 5of a die holder 6. In order to effect the reciprocation of the dieholder, a crank shaft 7 is rotatably mounted in bearings 8 carried bythe upper portion of the frame 2, whereby upon the rotation of the crankshaft, reciprocatory motion will be imparted to the die holder so as tomove the latter toward and away from the bed 3. v

In order to edect the rotation of the crank shaft, use is made of aclutch structure 9, which is of ordinary, construction and is so formedas to permit of but one cycle of operation on the part of the die holderunder any given operation. The clutch structure 9, per se, does not formthe subject matter of the present invention, as other well known devicesof equivalent nature may be successfully employed with equal facility incarrying out the aims of the present invention, but inasmuch as the useof the structure 9 disclosed admirably sets forth the operation of thepresent invention, the following description will be accordinglydirected thereto.

Loosely mounted upon the actuating end of the crank shaft 7 is a pulley10 and in order to connect the latter with the shaft 7 for uniformrotation, said shaft is provided with a longitudinally extending key-wain which is rotatably positioned a substantially semi-circular key 11,the latter being provided with a depending crank arm 12. A coil spring13 coiiperates with the arm 12 and tends to rotate the latter so thatthe key 11 will lie within the key-way provided in the crank shaft andalso in a reglstermg key-way 14c formed in the hub of the pulley 10.Obviously, when said key lies within both of said key-ways the pulley 10and the crank shaft 7 will be splined for simultaneous movement.

However, the tendency on the part of the spring 13 is counteracted bymeans of a pivoted dog 15, which through the agency of a. spring 16, isnormally maintained in the path of movement of the 12, so that as thelatter revolves it will'be caused engage with the dog 15 and retained insuch position as to cause the key 11 to remain wholly within theconfines of the longitudinal keyway formed in the shaft 7. Thus bylowering the dog 15 so that the same will be clear of the arm 12, saidspring 13 .may respond to its normal tendency and rotate the key 11,thus enabling the shaft and the pulley to rotate for a singlerevolution, as it will be manifest that when the dog is releasedfromengagement with the crank arm 12,and the latter has started on itsrotational movement, said dog will return to its normal position underthe influence exercised by the spring 16 and will thus be in position tocontact with the arm 12 when the latter completes a full turningmovement. It will thus be apparent that the structure 9 providesmechanism whereby the die holder 6 will be caused to complete but onecycle of movement under a given operation, and in this manner serves tominimize in uries to the machine operator by preventing undue movementon part of the die holder.

In order to operate the dog 15 so that the same may be released fromengagement with the arm 12, prior devices have employed foot controlledmeans for effecting this purpose. Practice has disclosed, however, thatwhen foot operated devices are utilized. in this connection, theoperator is inclined to become careless and accidentally press the foottreadle without having his hands clear of the holder 6. 'III this.manner many accidents have occurred on machines attainin a highproductive output. Therefore, t e present invention contemplates theprovision of a control mechanism B, which is of such construction as torequire both hands of the operator in effecting itssuccessfulmanipulation. Itwill thus follow that with both hands occupiedin operating the press at positions relatively remote with respect tothe die holder 6, accidents will be greatly minimized.

In its preferred form the mechanism B comprises a pivoted actuatinglever 17,

- tends, to force the latter in an upward di-- which is pivoted as at 18upon the frame 2, and theforward end of the lever is provided with ahandle 19 which extends through a vertically disposed slot 20 formed ina bracket 21, the latter-being rigidly. carried upon the forwardportions ofthe frame 2. A link 22 is'connected with the lever 17.inte'rmediately of its pivot 18 and its handle .19, and the upper endof said link .is similarly connected with the stop dog 15, whereby upon.the oscillation of the lever 17 simultaneous movement will be impartedto the dog 15, which latter in, turn controls the operatlon. .of theclutch structure 9. spring 23 coiiperates with the link 22 and rection,in order to retain the handle port1on of said lever in an elevatedposition connection 22.

The lever 17 is l ocked against movement normally by means of, a latch24, the latter being slidably mounted within a longitudinal opening 25formed in the bracket 21. The spring 26 is also positioned within saidopening and normally tends to force the latch 24 into the slot 20 sothat the latch will underlie the lever 17 and thus retain the latter ina locked position when elevated. In order to release the lever so thatthe same may be oscillated, the latch 24 is connected with a rod 27,which latter extends horizontally and is supported for sliding movementwithin the bracket 21 and within a similar bracket'28, located on theopposite side 'of the frame 2, said rod terminating in an offset handleportion 29, whereby the same may be grasped to effect release movementson part of the latch 24.

In operation, movement may be imparted to the die holder by grasping thehandle portion 29 of the rod 27, with one hand, so that the latch 24 maybe retracted from engagement with the lever 17, thus permitting thelatter to rock about its fulcrum 18. The handle 19 is grasped with theother hand, and when the latch has been properly retracted, said leveris forced downwardly and its movement in a similar direction is impartedto the do 15 by reason of the link imparted to the die holder 6, therotary.

movement of the crank shaft and the reciprocatory movement of the dieholder being s hereinbefore explained,-

compensated for by means of the usual pitman theory. After the movementof the die holder has beeninitiated, the-lever 17 is released sothat'the same will return to its upward position by virtue of theinfluence exercised by the spring 23 thereon, this upward movement ofthe lever also acting to return the dog 15 into the path of movement ofthe arm 12, thus causing theclutch structure to disconnect the shaft 7from the pulley .10 after a complete cycle of movement has beeneffected, this arrest of movement on part of the crank shaft '7, ofcourse, occurs w en the die holder is in its elevated position. Thelever. 17 is automatically locked in its upper position by means of thelatch 24, whic is provided with a'beveled underface '31, whereby whenthe lever is forced upwardly by the action of its spring,

A the same will force the latch inwardly until after the lever clearsthe same, and at this I juncture the latch is again forced outwardly bythe influence of its spring 26, so that the flat upper surface of thelatch will engage ean-me with the under edge of the lever so as toprevent the downward movement on part of the latter,

From the foregoing description, taken in connection with theaccompanying drawings, it will be apparent that an attachment ofconsiderable utility has been provided for power presses and similarautomatic machinery, said attachment serving to permit of theexpeditious operating of a press and reduces to a minimum the element ofphysical danger heretofore present in efi'ecting their operation. Itwill be observed that before the die holder can be reciprocated it isnecessary for the operator to remove .both hands from points contiguousto the holder in order to effect the operation of the control mechanism,and it is this fact essentially that serves to render the presentinvention successful in carrying out its safeguarding aims. In the eventof injury to one or the other of the springs 16 and 23, the remainingspring will still function to maintain related parts in operativepositions.

What I claim is In a power press, a rotatably mounted actuating shaft, apower delivering element capable of rotating independently of saidshaft, a manually operated clutch structure for connecting said shaftand element for rotation in unison, a pivoted stop member cooperativewith said clutch structure and normally serving to retain the shaftandpower delivering element out of driving relation, a manually operatedarm pivoted to the side of the press including a forwardly extendinghandle, a link between said arm and stop member, a spring cooperativewith said link and normally serving to maintain said arm inanelevatedposition and to retain said stop member in engagement with saidclutch structure, a spring pressed latch carried by the frontof saidpress and normally disposed to underlie said arm to prevent oscillationof the latter, said latch including a bevel nose portion and asubstantially fiat upper surface, and a slidably mounted actuating rodconnected with said latch disposed to extend transversely of said press,said rod terminating in a handle portion disposed in spaced relationshipfrom the handle portion of said' pivoted arm whereby both hands of theoperator will be required in efiecting the operation of the clutchoperating controlling mechanism.

In testimony whereof I affix my signature.

LEO L. PFElFE-R.

